The present invention relates to an aluminum can lid which is able to withstand pressure, having a pre-shaped opening or outlet in the lid surface and a ring-shaped groove at the transition from the lid surface to lid edge, the said lid being for cans containing carbonated drinks i.e. drinks containing carbon dioxide.
To improve the ability of a can lid, for example a lid on a can filled with a carbonated drink, to resist a relatively high pressure from within, a ring-shaped groove is usually provided at the transition between the lid surface and the lid edge. Also known, from the U.S. Pat. No. 3,417,898, is a lid without opening which features on the lid surface an outward domed, ring-shaped groove for further strengthening.
Increasing the resistance of the can lid to pressure from within is of economic interest inasmuch as the required ability to withstand such pressure can then be achieved with lids made from thinner sheet material.
It is therefore the principle object of the present invention to develop a can as set forth above characterized by improved ability to withstand pressure.